McIntosh C2500 Service Manual

TUBE PREAMPLIFIER
C2500
9
10
2
DISPLAY
751456 SCH 1 OF 4
GND (Pin 1)
5V (P in 2)
SI/SO (Pin 3)
STB ( Pin 4)
SCK (Pin 6 )
.01µFC207
.01µF
C206
DGND
DGND
VFD-GND
INPUT_B
INPUT_A
22.1
R11
47µF
C1
IR SENSOR
2
1
3
Vcc
Vout
GND
MT1
.1µF
C2
1K
R45
3.3V
22.1KR29
22.1K
R30
22.1K
R28
22.1K
R34
3.3V BU
J9:18
J9:15
J9:12
J9:16
J9:17
J9:13
J9:10
J9:11
J9:14
J9:9
J9:6
J9:3
J9:4
J9:5
J9:7
J9:1
J9:8
J9:2
INPUT_A
INPUT_B
LEFT PB AD
VFD 5V
VFD SCL
VFD SDA
VFD CE
VFD CE
FRON T_IR
I2C_SCL
I2C_SDA
VFD 5V
VFD SDA
VFD SCL
.1µFC6
DGND
3.3V
.1µFC7
DGND
3.3V
3.3V BU
BYPASS
PROC
DS2
3
DS24
DS18
STANDBY/ON
MH2
ADC-VREF-L
3.3V
VFD 5V
TRIM
DS17
750932 = 058195 + 9 pin conn (117986)
4
2
1
3
Vcc
GND
5
U4
4
2
1
3
Vcc
GND
5
U5
SELECTOR
INPUT
5V
GND
6
B
1
C
4
A
5
GND
7
S1
146261
ILLUMINATION
FRONT PANEL
DS6 DS4
3
1
2
Q1
150
R14
150
R19
DS2
2.21K
R16
150
R15
PANEL_LAMP
Q3
7
VSS
8
Q1
5
A1
2
A2
3
Q4
9
Q5
10
Q7
12
SDA
15
SCL
14
Q2
6
A0
1
Q0
4
Q6
11
VDD
16
NC
13
U30
22.1K
R202
22.1K
R201
22.1K
R210
22.1K
R209
3.3V BU
22.1
R211
22.1
R212
22.1K
R203
22.1K
R204
1K
R220
1K
R213
1K
R214
1K
R216
1K
R218
Address=3
.1µF
C80
OFF
ON
OFF
ON
OFF
ON
OFF
ON
3.3V BU
I2C_SDA
I2C_SCL
5V
DS7
150
R2
DS8
150
R1
DS9
OUT1
DS10
OUT2
3.3V
3.3V
3.3V
3.3V 3.3V
PANEL_LAMP
3.3V BU
.1µF
C66
4
2
1
3 5
Vcc
GND
U25
47µF
C18
.1µF
C19
10µH
L1
47µF
C23
VOL-B
VOL-A
OFF
ON
22.1
R69
22.1
R70
SDA (SI/SO )
CE (S TB)
SCL ( SCK)
J1:2J1:7 J1:1J1:5 J1:4J1:6J1:9 J1:3J1:8
Daughter PCB
J12:12J12:11
J12:10J12:9
J12:8J12:7
J12:6J12:5
J12:4J12:3
J12:2J12:1
J11:12
J11:11
J11:10
J11:9
J11:8
J11:7
J11:6
J11:5
J11:4J11:3
J11:2J11:1
B
A
179
4 6
12
Ground
J13:4
MH1
052139 (146260)
J13:3
J13:2
J13:1
CONTROL
VOLUME
MH12
MH9
METER LEDs ON
METER MUTE
.1µF
C8
3.3V
4
2
1
3
Vcc
GND
5
U6
3.3V BU
.1µF
C9
4
2
1
3 5
Vcc
GND
U7
22.1
R8
J7:1
J7:2
J7:3
J7:4
J7:5
J7:6
J7:7
J7:8
J7:9
J7:10
J7:11
J7:12
3.3V BU
VOL-B
ON/RESET
5V
5V
ADC-VREF-R
RIGHT PB AD
VOL-A
3.3V
FRONT_IR
SP1
-15V
15V
To Control PCB
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
2
3
1
J17
J16:1
J16:2
J16:5
.1µF
C119
MP2 MP1
GP1
J16:4
Tip
Ring
GND
Cable 173167, 1-1 Pinout.
Headphone daughter PCB
2X20 VFD ASSY
Left PB
Right PB
Volume Logo
Input
DS1

McIntosh C2500 Specifications

General

Total Harmonic Distortion	0.08%
Signal to Noise Ratio	100dB
Rated Output Voltage	2.5V unbalanced, 5V balanced
Maximum Output Voltage	8V unbalanced, 16V balanced
High Level Voltage Gain	15dB
Type	Vacuum Tube Preamplifier
Inputs	6 unbalanced, 2 balanced, 1 phono MC, 1 phono MM
Outputs	3 unbalanced, 2 balanced
Weight	29 lbs (13.2 kg)
Input Impedance	47k ohms
Phono Voltage Gain	40dB (MM), 60dB (MC)
Frequency Response	+0, -0.5dB from 20Hz to 20, 000Hz +0, -3dB from 10Hz to 100, 000Hz